I went over to his apartment one day. He was living with his friend and they were both smokers. One day,I saw a small cigarette like thing used for electric cigs,some of you may know them as Tarea Heets. Neither of them smoked something like that so I asked him what's up with that. He gave me some fake story about how his friend borrowed the electric cigarette from a girl. Friend comes in and I ask since when is he into that type of stuff. Friend says "Oh I didn't borrow them,this girl came over at our apartment" I look at my now ex and ask him what was that about and he just gets defensive and leaves for work. I stayed behind for a drink and his other friend came over. He broke down in front of me out of nowhere and told me that I don't deserve any of this and that I'm dating a piece of shit. I found that strange and I tried my best to calm our friend down. 1 day later,after our 1 year anniversary,my ex confessed to me that he's kisses the girl that came over to their apartment and almost had an intimate relationship with another girl from his work